Yeahh the Rotti has a more powerful bite than a pitbull. But to be honest, that isnt suprising is it ? given that a Rotti is normally twice the size ? I think the national geographic tested a mastiff which then had a bite force of over 500 pound, because the dog and its head is bigger again.

I think makes a dog protential dangerous and used in "dog fighting", ect a dogs agressiveness and willing to fight, and gameness. So hence why a pitbull is seen as more a threat then a bullmastiff for example, even though the bite force is only half.